Outcomes of Acute Conduction Abnormalities Following Transcatheter Aortic Valve Implantation With a Balloon Expandable Valve and Predictors of Delayed Conduction System Abnormalities in Follow-up.

Transcatheter aortic valve implantation (TAVI) is an acceptable treatment for severe aortic stenosis in high or intermediate risk patients. Conduction abnormalities are a known complication of TAVI. Most abnormalities occur perioperatively but can develop later. The predictors of delayed conduction abnormalities are unknown. Patients who underwent TAVI at our institution were reviewed. Patients with a pre-existing pacemaker were excluded. Baseline, in-hospital, and 30-day follow-up ECGs were reviewed. Patient and procedural characteristics were analyzed to look for predictors of acute and delayed abnormalities. Ninety-eight patients were included. All valves implanted were balloon expandable, most commonly SAPIEN S3 (78%). Thirty-seven (37.7%) patients developed abnormalities before discharge. Of these patients, 20 (57.1%) had complete resolution at 30-day follow-up. No patients with new conduction abnormalities during hospitalization had additional abnormalities at 30-day follow-up. Five (5.1%) patients developed new conduction abnormalities following discharge. Overall, 22 (22.4%) patients had conduction abnormalities at 30-day follow-up which were not present at baseline. Predilatation (p = 0.003), higher ratios of balloon (p = 0.03) or valve (p = 0.05) size to left ventricular outflow tract, and previous myocardial infarction (p = 0.034) were predictive of acute conduction abnormalities. Baseline right bundle branch block (p = 0.002), longer baseline (p <0.001) and discharge (p = 0.004) QRS duration, moderate, or severe aortic insufficiency (p = 0.002) and atrial fibrillation (p = 0.031) were predictors of new conduction abnormalities after discharge. In conclusion, most new in-hospital conduction abnormalities resolve by 30-day follow-up. In-hospital conduction abnormalities are related to technical aspects of TAVI while delayed conduction abnormalities are related to baseline conduction system disease.